Mutations in mitochondrial DNA (mtDNA) have been described in almost all tumor types. It has been postulated that accumulation of mtDNA mutations could alter mitochondrial function in tumor cells and confer them clonal selective advantage. Nevertheless, its causal involvement in tumorigenesis is still uncertain. In the present study and taking advantage of next-generation sequencing, we have done a complete genomic characterization of the mtDNA genome sequence of a large set of tumor samples. Our data show evidence that mtDNA mutations likely confer a selective advantage to tumor cells. Additionally, we observe a mutational profi le which does not correspond with the described for oxidative stress which is assumed to be the main mtDNA mutagen. Finally, we describe a significant strand bias on the distribution of the mutations that could evidence the presence of new DNA repair mechanisms processes not reported until now in the mitochondria. These findings could off er new insights on the biology of the mitochondria and support its functional involvement in tumorigenesis which could improve the diagnosis and treatment of cancer patients.

Resumen del póster presentado al XL Congreso de la Sociedad Española de Bioquímica y Biología Molecular (SEBBM), celebrado en Barcelona del 23 al 26 de octubre de 2017.-- Quevedo, Laura et al.

Peer reviewed